Apparatus and Method for Axially Transferring Fluids to a Plurality of Components

ABSTRACT

An apparatus for axially transferring fluid may comprise an elongated shaft defining a first fluid passageway axially therethrough and a second fluid passageway from an outer surface thereof to the first fluid passageway. An elongated tube member defines an outer surface that is received within the first fluid passageway and a third fluid passageway axially therethrough. A plurality of axial channels are defined between the tube member and the first fluid passageway or along the tube member separately from the third fluid passageway. At least one of the plurality of axial channels define a first opening near one end thereof that receives fluid from a source of fluid and a second opening axially spaced apart from the first opening and that aligns with the second fluid passageway such that fluid may be transferred by the at least one fluid passageway from the source of fluid through the second fluid passageway.

FIELD OF THE INVENTION

The present invention relates generally to structures and techniques fortransferring fluids from one or more points to one or more other pointsalong an elongated path, and more specifically to structures andtechniques for axially transferring fluids to a plurality of components.

BACKGROUND

It is generally known to control certain types of actuators usingpressurized fluid. As one specific example, it is generally known tocontrol friction devices, e.g., clutches, in automatic transmissionsusing pressurized fluid. It is desirable in such applications totransfer fluid from one or more points in or into an apparatus or systemto one or more other points in such an apparatus or system. It isfurther desirable to axially transfer such fluids in an apparatus orsystem along an elongated path to a plurality of components of theapparatus or system.

SUMMARY

The present invention may comprise one or more of the features recitedin the attached claims, and/or one or more of the following features andcombinations thereof. An apparatus for axially transferring fluid maycomprise an elongated shaft defining a first fluid passageway axiallytherethrough and a second fluid passageway from an outer surface thereofto the first fluid passageway. An elongated tube member may define anouter surface and a third fluid passageway axially therethrough. Theouter surface of the tube member may be configured to be received withinthe first fluid passageway of the shaft. A plurality of axial channelsmay be defined between the tube member and the first fluid passageway ordefined by and along the tube member separately from the third fluidpassageway. At least one of the plurality of axial channels may define afirst opening near one end thereof that receives fluid from a source offluid and a second opening axially spaced apart from the first openingand that aligns with the second fluid passageway such that fluid can beaxially transferred by the at least one fluid passageway from the sourceof fluid through the second fluid passageway defined through the shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional diagram of a portion of an automatictransmission showing one illustrative embodiment of an apparatus foraxially transferring fluids along an elongated path to a plurality oftransmission components.

FIG. 2 is a cross-sectional view of the apparatus of FIG. 1 as viewedalong section lines 2-2.

FIG. 3 is a cross-sectional diagram similar to FIG. 1 and illustratingan alternate embodiment of the tube member illustrated in FIG. 1.

FIG. 4 is a cross-sectional diagram of a portion of an automatictransmission showing an alternative embodiment of an apparatus foraxially transferring fluids along an elongated path to a plurality oftransmission components.

FIG. 5 is a cross-sectional view of the apparatus of FIG. 4 as viewedalong section lines 5-5.

FIG. 6 is a cross-sectional diagram of yet another alternativeembodiment of an apparatus for axially transferring fluids along anelongated path to a plurality of components.

FIG. 7 is a cross-sectional view of the elongated path of the apparatusof FIG. 6.

FIG. 8 is a cross-sectional view of the elongated path of FIG. 7 asviewed along section lines 8-8.

FIG. 9 is a cross-sectional view of the tube member illustrated in FIG.6.

FIG. 10 is a cross-sectional view of the apparatus of FIG. 6 as viewedalong section lines 10-10.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to a number of illustrativeembodiments shown in the attached drawings and specific language will beused to describe the same.

Referring now to FIG. 1, a cross-sectional diagram is shown of a portionof an automatic transmission showing one illustrative embodiment of anapparatus 100 for axially transferring fluids along an elongated path toa plurality of transmission components. In the illustrated embodiment,the elongated path takes the form of a shaft 110 defining a bore 113therethrough. Between one end 112 of the shaft 110 and a wall portion115 of the bore 116, the bore 113 defines one diameter 114, and betweenthe wall portion 115 and an opposite end (not shown) of the shaft 110,the bore 113 defines another diameter 116, wherein the diameter 114 isgenerally larger than the diameter 116. Illustratively, the diameter 114is sized to accommodate axial insertion of a tube member 120 therein.Along the shaft 110, a number of bores extend through an exteriorsurface thereof to the bore 113. In the illustrated embodiment, two suchbores 118A and 118B are identified. In one embodiment, the shaft formsone component of a transmission for a mobile vehicle, and the bores 118Aand 118B each lead to a fluid input of a fluid-controlled frictiondevice, e.g., a friction clutch, although this disclosure contemplatesembodiments in which the apparatus 100 is configured to axially transferfluid to other components. In any case, the shaft 110 is illustrativelyformed of a conventional metal, combination of metals or a metalcomposite, although this disclosure contemplates other embodiments inwhich the shaft 110 is formed of other materials and/or materialcombinations.

The tube member 120 is an elongated tubular structure that is axiallyreceived within the bore 113, e.g., between the end 112 of the shaft 110and the wall portion 115 as illustrated in FIG. 1. Referring to FIG. 2,a cross-sectional view of one embodiment of the tube member 120 is shownas viewed through section lines 2-2 of FIG. 1. In the illustratedembodiment, the tube member 120 is formed of a conventional hollow,metal tube or bar stock with an inner surface of one tube 124selectively joined to an outer surface of another tube 122. Generally,the inner surface of the tube 124 has a diameter that is larger than thediameter of the outer surface of the tube 122. In the illustratedembodiment, one portion 126 of the inner surface of the tube 124 islongitudinally joined to and along a corresponding portion of the outersurface of the tube 122, and another portion 128 of the inner surface ofthe tube 124 is longitudinally joined to and along a correspondingportion of the outer surface of the tube 122. Between the portions 126and 128, the remaining portions 130 and 132 of the tube 124 and thecorresponding portions of the outer surface of the tube 122 defineseparate, i.e., not fluidly connected, longitudinal or axial channels orpassageways 134 and 136 respectively therebetween that extendlongitudinally or axially along the tube member 120.

As illustrated in FIG. 1, the ends of the tubes 122 and 124 arecircumferentially joined at 144 and 146. In the illustrated embodiment,the ends of the tube 122 and 124 are joined by deforming the oppositeends of the tube 124 toward the corresponding ends of the tube 122 andthen joining the ends of the tubes 122 and 124 using one or moreconventional joining techniques. In an alternate embodiment of theapparatus 100′ illustrated in FIG. 3, the ends of the tubes 122 and 124of the tube member 120′ adjacent to the end 112 of the shaft 110 arejoined at 146′ by deforming the end of the tube 122 toward the end ofthe tube 124 and the joining the ends of the tubes 122 and 124 using oneor more conventional joining techniques.

The tube member 120 is illustratively formed by selectively bending orpressing the tube 124, and the tubes 122 and 124 may be axially andcircumferentially joined using any one or more conventional joiningmedia and/or techniques. Examples include, but are not limited to,welding, spot welding, laser welding, using one or more adhesives and/orconventional fastening members, or the like.

As further illustrated in FIG. 2, the portions 126 and 128 of the outertube 124 each define a separate axial channel or passageway 138 and 140respectively between the corresponding portion 126/128 and the innerdiameter 114 of the bore 113 of the shaft 110. The tube member 120 isillustratively press-fit into the bore 113 as illustrated in FIG. 1, andin this embodiment, fluid may pass between the channels 138 and 140. Inthis embodiment, as illustrated in FIG. 2, the tube member 120 and shaft110 thus cooperate to axially define four separate fluid channels orpassageways therethrough; the two channels 134 and 136 defined betweenthe tubes 122 and 124, the channels 138 and 140 defined between the tube124 and the inner diameter 114 of the bore 113 of the shaft 110 and apassageway 142 defined axially through the tube 122. In an alternateembodiment, sealing structures may be positioned between the portions130 and 132 of the tube 124 and the inner diameter 114 of the bore 113of the shaft 110 so that fluid may not pass between the channels 138 and140. In this embodiment, the tube member 120 and the shaft 110 thuscooperate to axially define 5 separate fluid channels or passagewaystherethrough, the four channels 134, 136, 138 and 140, and thepassageway 142. Although the channels 134 and 136 are illustrated inFIG. 2 as being asymmetrically positioned about the outer surface of thetube 122, it will be understood that the channels 134 and 136 mayalternatively be positioned symmetrically about the outer surface of thetube 122. It will be further understood that while the tube member 122illustrated in FIG. 2 defines two channels 134 and 136 between the tubes124 and 122, this disclosure contemplates that more or fewer suchchannels may be alternatively formed between the tubes 122 and 124.

Referring again to FIG. 1, the inner tube 122 defines an opening 148into the channel 134, and the outer tube 124 also defines an opening 150into the channel 134 that is aligned with the bore 118A formed throughthe shaft 110. Fluid may thus pass axially along the tube member 120through the channel 134 between the openings 148 and 150.

The apparatus 100 further includes a manifold 160 that defines a numberof fluid passageways therethrough. In the illustrated embodiment, forexample, a fluid passageway 162 extends into the manifold 160 and isfluidly coupled to another fluid passageway 165 that is fluidly coupledto the bore 113 of the shaft 110. Another fluid passageway 164 extendsinto the manifold 160 and is fluidly coupled to another fluid passageway168 that extends at least partially radially about the manifold 160. Yetanother fluid passageway 166 extends into the manifold 160 and isfluidly coupled to still another fluid passageway 170 that likewiseextends at least partially radially about the manifold 160 separatelyfrom the fluid passageway 168. In the illustrated embodiment, the fluidpassageway 170 is aligned with the opening 148 formed through the tube122 and extending into the channel 134. In the illustrated embodiment,fluid may thus be routed from the fluid passageway 166 of the manifold160 through the bore 118A of the shaft 110 via the fluid passageways170, 148, 134, 150 and 118A as illustrated in FIG. 1.

In the illustrated embodiment, the manifold 160 is held stationary andthe combination shaft 110 and tube member 120 rotate together about themanifold 160. The manifold 160 includes a number of conventional sealingmembers, e.g., sealing rings, 172 that are positioned as illustrated inFIG. 1 to keep fluids from axially leaking from the fluid passageways168 and 170 along the inner surface of the tube 122. It will beunderstood, however, that this disclosure contemplates embodiments inwhich the combination shaft 110 and tube member 120 are held stationaryand the manifold 160 rotates relative thereto, in which the manifold 160and tube member 120 are stationary and the shaft 110 rotates about thecombination, in which the shaft 110 is stationary and the combinationmanifold 160 and tube member 120 rotate about the shaft 110, or in whichthe combination shaft 110 and tube member 120 and the manifold 160 areall stationary.

In one specific embodiment of the apparatus 100 illustrated in FIG. 1,at least one of the channels 134 and 136 is illustratively used to routepressurized fluid to one or more friction devices mounted to or fluidlycoupled to the shaft 110, and the channels 138 and 140 and the fluidpassageway 142, as well as perhaps one of the channels 134 and 136, areillustratively used to route lubricating fluid to one or more frictiondevices, and/or to the tube member 120 and shaft 110 combination and/orto one or more other components.

Referring now to FIG. 4, a cross-sectional diagram is shown of a portionof an automatic transmission showing another illustrative embodiment ofan apparatus 200 for axially transferring fluids along an elongated pathto a plurality of transmission components. In FIG. 5, a cross-sectionalview of the tube member 220 is shown. Many of the components in theapparatus 200 are identical to those illustrated and describedhereinabove with respect to the apparatus 100, and like numbers (plus100) are used in FIG. 4 to identify like components. In the embodimentillustrated in FIGS. 4 and 5, the tube member 220 differs from the tubemember 120 in that the tube member 220 defines an additional fluidchannel or passageway between the tubes 222 and 224, for a total ofthree such fluid channels or passageways 234, 236 and 238, and anadditional fluid channel or passageway between the outer tube 224 andthe inner diameter 214 of the bore 213 of the shaft 210 for a total ofthree such fluid channels or passageways 240A, 240B and 240C. The innerdiameter of the tube 222 defines an additional fluid channel orpassageway 242. In the illustrated embodiment, the inner tube 222additionally defines an air bleed hole 245 therethrough.

In the embodiment illustrated in FIG. 4, a fluid source 180 is mountedto the manifold 260. Fluid entering a fluid port 282 may enter the fluidpassageway 264 of the manifold 260, and fluid entering the fluid port284 may enter either of the fluid passageways 262 and 266. In theillustrated embodiment, two friction devices 290 and 310 are mounted tothe outer surface of the shaft 210, and the shaft 210 defines a numberof bores therethrough between the outer and inner surface thereof forfluid coupling of the devices 290 and 310 to the bore 213 of the shaft210. For example, the friction device 290 includes a friction apparatus292, e.g., a clutch pack, which is fluidly coupled to a bore 300 via afluid chamber 298. The bore 300 thus fluidly couples the frictionapparatus 292 to the bore 213 of the shaft 210. The friction device 290further includes a friction device piston chamber 295 which is fluidlycoupled to a bore 297 that fluidly couples the chamber 295 to the bore213 of the shaft 210. The friction device 290 further includes a balancecavity 294 which is fluidly coupled to a bore 296 that fluidly couplesthe cavity 294 to the bore 213 of the shaft 210. The balance cavity 294is also fluidly coupled to the bore 213 via a balance cavity feed bore302. The friction device 310 likewise includes a friction apparatus 312,e.g., a clutch pack, and a friction device piston chamber 315. Thechamber 315 is fluidly coupled to a bore 316 that fluidly couples thechamber 316 to the bore 213 of the shaft 210. The friction device 310further includes a balance cavity 318 which is fluidly coupled to a bore320 that fluidly couples the cavity 318 to the bore 213 of the shaft210. The balance cavity 318 is also fluidly coupled to the bore 213 viaa balance cavity feed bore 322.

In the embodiment illustrated in FIG. 4, the opening defined by the tube222 to the fluid channel 234 is aligned with the fluid passageway 268and the opening defined by the tube 224 into the fluid channel 234 isaligned with the bore 316 so that fluid entering the port 282 and thefluid passageway 264 is routed axially along the tube member 222 to theclutch piston chamber 315 via the fluid passageway 268, the fluidchannel 234 and the bore 316. The fluid channel 234 is thus used totransmit fluid, e.g., oil, from the stationary manifold 260 to thefriction device piston of the friction device 310 for actuation controlof the friction device 310. Another of the fluid channels 236 or 238 isused in like manner to transmit fluid, e.g., oil, from the stationarymanifold 260 to the friction device piston of the friction device 290for actuation control thereof. The third fluid channel 236 or 238illustratively serves as a fluid overflow cavity that reduces the innerdiameter of each annulus of rotating fluid, e.g., oil, to centrifugallybalance the friction device apply pistons. For example, in theillustrated embodiment, the friction device balance cavities of thefriction devices, e.g., 290 and 310, are fed from pressurizedlubrication oil in the passages, e.g., the fluid channel 240C, betweenthe tube member 220 and the inner surface 214 of the bore 213 of theshaft 210 (e.g., which is supplied via the fluid passageway 262 andthrough the fluid passageway or channel 242 of the tube member 220).Once the balance cavities 294 and 314 are filled, the fluid, e.g., oil,then flows through bores (not shown) formed through the shaft 210 andinto the third fluid channel 236 or 238. The fluid, e.g., oil, thenexits the third fluid channel 236 or 238 into one or more of thechambers 298 and 318 to cool one or more of the corresponding frictionapparatuses 292 and 310. This reduced diameter of the annulus ofrotating balance fluid, e.g., oil, creates a higher pressure headopposing the pressure head created on the apply side of the frictiondevice piston which allows the shaft 210 to rotate at a higher speedbefore the friction device apply piston begins to stroke. A higher shaftspeed allows lower torque to be transmitted through the shaft 210 whichreduces gear and shaft loads as well as a corresponding size of suchcomponents.

Referring now to FIGS. 6-10, cross-sectional diagrams are shown of yetanother alternative embodiment of an apparatus 400 for axiallytransferring fluids along an elongated path to a plurality ofcomponents. The apparatus 400 may be configured for use in either of theembodiments illustrated in FIGS. 1-5, or may alternatively be configuredfor use in one or more other applications. In the illustratedembodiment, as shown in FIG. 6, the apparatus 400 includes a shaft 410having opposite ends 412 and 413, and defining a bore 414 therethrough.An elongated tube member 420 is configured to be axially received withinthe bore 414 of the shaft 410 such that one end of the tube member 420is positioned adjacent to the end 412 of the shaft 410.

As illustrated in FIGS. 6-8, the portion of the bore 414 that receivesthe tube member 420 defines a number of axial channels therein.Referring to FIG. 8, for example, the inner surface 414 of the shaft 410defines four channels 418A-418D therein that are symmetrically spacedfrom each other about the circumference of the bore 414. It will beappreciated, however, that more or fewer such channels, symmetricallyspaced or otherwise, may alternatively be formed in the inner surface414 of the shaft 410.

The tube member 420 is, as illustrated in FIG. 9, a single, hollow tubedefining a bore 422 therethrough. In the illustrated embodiment, thetube member 420 is circular in cross-section and has constant diameterinner and outer surfaces. The apparatus 400 is assembled by insertingthe tube member 420 into the bore 414 at the end 412 of the shaft 410.The tube member 420 and the shaft 410 are configured such that the outersurface of the tube member 420 forms an interference fit with the bore414 defined through the shaft 410, and the terminal ends of the tubemember 420 form seals with the bore 414. The outer surface of the tubemember 420 and the surface of the bore 414 form separate fluid transfercavities or channels, e.g., 418A-418D, through which fluid can beaxially transferred.

While the invention has been illustrated and described in detail in theforegoing drawings and description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly illustrative embodiments thereof have been shown and described andthat all changes and modifications that come within the spirit of theinvention are desired to be protected. For example, while the variousembodiments of the shaft 110, 210 and 410 and the tube member 120, 220and 420 are illustrated as being generally circular in cross-section,this disclosure contemplates that any of the embodiments of the shaftand the tube member may alternatively have cross-sections other thancircular. Moreover, it will be understood that the fluid channels orpassageways defined between the inner and outer tubes in the embodimentsillustrated and described with respect to FIGS. 1-5 may be symmetricallyor non-symmetrically positioned about the tube members, and that thechannels formed in the shaft of the embodiment illustrated and describedwith respect to FIGS. 6-10 may by symmetrically or non-symmetricallypositioned about the inner surface of the shaft.

1. An apparatus for axially transferring fluid, comprising: an elongatedshaft defining a first fluid passageway axially therethrough and asecond fluid passageway from an outer surface thereof to the first fluidpassageway, an elongated tube member defining an outer surface and athird fluid passageway axially therethrough, the outer surface of thetube member configured to be received within the first fluid passagewayof the shaft, and a plurality of axial channels defined between the tubemember and the first fluid passageway or defined by and along the tubemember separately from the third fluid passageway, at least one of theplurality of axial channels defining a first opening near one endthereof that receives fluid from a source of fluid and a second openingaxially spaced apart from the first opening and that aligns with thesecond fluid passageway such that fluid can be axially transferred bythe at least one fluid passageway from the source of fluid through thesecond fluid passageway defined through the shaft.